A magnetic recording medium may include a patterned medium above which a read-write head flies at a flying height of 10 nm or less. Consequently, the surface properties of the patterned medium are important. For stable flight of the read-write head over the patterned medium, it is necessary to completely eliminate residual hard masks, which are required as part of the manufacturing process. Also, it is necessary for the patterned medium to have a very smooth surface, which is accomplished by eliminating particles that may be present on the surface after a stripping process. Methods of eliminating hard masks from a patterned medium include a dry strip process that performs the strip in a vacuum and a wet strip process that performs the strip using a liquid solution.
The wet strip process is effective in removing particles; however, there are some drawbacks. In such a process, a strip agent contacts an exposed recording layer for the duration of the strip process, which can damage the recording layer. Also, a substrate with a recording layer that has been processed for a strip treatment needs to be exposed to air, so that a layer of oxidation might be formed on the exposed surface of the recording layer. In contrast, in a dry strip process, it is difficult to completely remove particles that are made of different materials, and consequently the recording layer may be damaged during a dry strip process when process is performed in a way that completely removes particles.
Also, in a case where a wet strip is performed before a pattern is transferred to a dry strip layer of a magnetic recording medium on which a dry strip layer, a wet strip layer, and/or a patterning layer are laminated, the pattern is completely stripped. In contrast, in a case where a pattern is transferred to the dry strip layer, the surface of the magnetic recording medium is exposed, and the magnetic recording layer may be damaged by the solution used in the wet strip process.